// Workers AI · dad joke modeWhy was lanthanide tribromide sad? It was a bromide.
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Lanthanide tribromides are a family of inorganic compounds with the formula LnBr3, where Ln stands for a lanthanide metal. The tribromides are similar to the more widely used lanthanide trichlorides. They exist as anhydrous solids and as hydrates. For the hydrates, three structural motifs are recognized: [Ln2(μ-Br)2(H2O)14]Br4, [LnBr2(H2O)6]Br, and [Ln(H2O)8]Br3. The former two are also observed for the lanthanum trichlorides, but the last motif is unique to the bromides.
They can be prepared by heating the hydrated lanthanide bromides with excess ammonium bromide under an atmosphere of hydrogen bromide.[1][2]
Inventory
[edit]| Ln | formula unit | relationship to hydrated trichloride |
|---|---|---|
| LaBr3 | [La2(μ-Br)2(H2O)14]Br4 | Like the corresponding chloride |
| CeBr3 | [Ce2(μ-Br)2(H2O)14]Br4 | Like the corresponding chloride |
| PrBr3 | [PrBr2(H2O)6]Br | Like the corresponding chloride |
| NdBr3 | [NdBr2(H2O)6]Br | Like the corresponding chloride |
| PmBr3 | [PmBr2(H2O)6]Br | Like the corresponding chloride |
| SmBr3 | [SmBr2(H2O)6]Br | Like the corresponding chloride |
| EuBr3 | [EuBr2(H2O)6]Br | Like the corresponding chloride |
| GdBr3 | [GdBr2(H2O)6]Br | Like the corresponding chloride |
| TbBr3 | [TbBr2(H2O)6]Br | Like the corresponding chloride |
| DyBr3 | [DyBr2(H2O)6]Br | Like the corresponding chloride |
| HoBr3 | [Ho(H2O)8]Br3 | chloride adopts [LnCl2(H2O)6]Cl motif |
| ErBr3 | [Er(H2O)8]Br3 | chloride adopts [LnCl2(H2O)6]Cl motif |
| TmBr3 | [Tm(H2O)8]Br3 | chloride adopts [LnCl2(H2O)6]Cl motif |
| YbBr3 | [Yb(H2O)8]Br3 | chloride adopts [LnCl2(H2O)6]Cl motif |
| LuBr3 | [Lu(H2O)8]Br3 | chloride adopts [LnCl2(H2O)6]Cl motif |
References
[edit]- ↑ K. Wetzel (1963). "Rare Earth Tribromides". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2. NY, NY: Academic Press. p. 1149.
- ↑ Gerd Meyer; Siegfried Dötsch; Thomas Staffel (1987). "The Ammonium-Bromide Route to Anhydrous Rare Earth Bromides MBr3". Journal of the Less Common Metals. 127: 155–160. doi:10.1016/0022-5088(87)90372-9. Retrieved 2020-05-29.
- ↑ Semenova, Lioubov I.; Junk, Peter C.; Skelton, Brian W.; White, Allan H. (1999). "Structural Systematics of Rare Earth Complexes. XVI ('Maximally') Hydrated Rare Earth( III ) Bromides". Australian Journal of Chemistry. 52 (6): 531–538. doi:10.1071/CH98047.